In a typical windrower, a harvesting vehicle supports a header thereon such that the header can be operated in a floating mode engaged upon the ground using a floating mechanism which carries most of the weight of the header on the harvester vehicle while enabling the header to float in height relative to the harvester vehicle so that the header can follow the contours of the ground with the engagement of the ground providing the remaining lifting forces for supporting the header. One particular problem associated with a float mechanism of this type is the potential for damage to the header if the header is connected to the harvester vehicle but the float remains inactive. Alternatively, when disconnecting the header, maintaining the float mechanism in an active state places considerable stress on the mechanical mounts which can also result in damage to the header.